Wait until you can see the leaves. The shoots may be from the tree peony. When you planted the tp if you planted deep some of the stem contains both root and stem cells. Depending on conditions and other more scientific reasons the cells become active.

When the leaves have unfurled compare with both tree and herbaceaous plant leaves.

I agree, wait and see. I have several growing new shoots from the base and they are the tree peony. Al

I have to say , I used to be a bit concerned seeing those basal shoots, but all have p;roven to be from the grafted tops and none ever from the rootstock. I think provided, they were planted deeply enough , the rootstocks don't tend to send up shoots very often. I would add count your blessings if they are as expected tree peony shoots, since it's not all that bad to have extra new shoots comming up for fuller looking plants and some insurance least you sometimes lose one of the older main trunks. That happens rarely for unknown reasons, so having extra shoots is desirable in my book. If you're looking for a "formal or standard" with a single trunk, which is possible, you can remove the extra shoots, though I'd not bother. Also , I'd add, if you wait a bit and do have regular herbaceous peonies to compare the leaves for an ID, they are quite different once the leaves have grown a bit larger. I can easily see the difference in the way the tree ones and herbaceous ones look in leaf form and shape.